For two vertices u and v in a strong digraph D, the strong distance
between u and v is the minimum number of arcs of a strong subdigraph
of D containing u and v. The strong eccentricity of a vertex v of
D is the strong distance between v and a vertex farthest from v.
The strong diameter (strong radius) of D is the maximum (minimum)
strong eccentricity among all vertices of D. The lower orientable strong
diameter (lower orientable strong radius), sdiam(G) ( srad(G) ), of a
2-edge-connected graph G is the minimum strong diameter (minimum
strong radius) over all strong orientations of G. In this paper, a
conjecture of Chen and Guo is disproved by proving sdiam(K3 □ K3) =
sdiam(K3 □K4) = 5, sdiam(Km □ Pn) is determined, sdiam(G) and
srad(G) for cycle vertex multiplications are computed, and some results
concerning sdiam(G) are described.